|
- #include <math.h>
- #include <stdlib.h>
- #include <string.h>
- #include <stdio.h>
- #include <complex.h>
- #ifdef complex
- #undef complex
- #endif
- #ifdef I
- #undef I
- #endif
-
- #if defined(_WIN64)
- typedef long long BLASLONG;
- typedef unsigned long long BLASULONG;
- #else
- typedef long BLASLONG;
- typedef unsigned long BLASULONG;
- #endif
-
- #ifdef LAPACK_ILP64
- typedef BLASLONG blasint;
- #if defined(_WIN64)
- #define blasabs(x) llabs(x)
- #else
- #define blasabs(x) labs(x)
- #endif
- #else
- typedef int blasint;
- #define blasabs(x) abs(x)
- #endif
-
- typedef blasint integer;
-
- typedef unsigned int uinteger;
- typedef char *address;
- typedef short int shortint;
- typedef float real;
- typedef double doublereal;
- typedef struct { real r, i; } complex;
- typedef struct { doublereal r, i; } doublecomplex;
- #ifdef _MSC_VER
- static inline _Fcomplex Cf(complex *z) {_Fcomplex zz={z->r , z->i}; return zz;}
- static inline _Dcomplex Cd(doublecomplex *z) {_Dcomplex zz={z->r , z->i};return zz;}
- static inline _Fcomplex * _pCf(complex *z) {return (_Fcomplex*)z;}
- static inline _Dcomplex * _pCd(doublecomplex *z) {return (_Dcomplex*)z;}
- #else
- static inline _Complex float Cf(complex *z) {return z->r + z->i*_Complex_I;}
- static inline _Complex double Cd(doublecomplex *z) {return z->r + z->i*_Complex_I;}
- static inline _Complex float * _pCf(complex *z) {return (_Complex float*)z;}
- static inline _Complex double * _pCd(doublecomplex *z) {return (_Complex double*)z;}
- #endif
- #define pCf(z) (*_pCf(z))
- #define pCd(z) (*_pCd(z))
- typedef int logical;
- typedef short int shortlogical;
- typedef char logical1;
- typedef char integer1;
-
- #define TRUE_ (1)
- #define FALSE_ (0)
-
- /* Extern is for use with -E */
- #ifndef Extern
- #define Extern extern
- #endif
-
- /* I/O stuff */
-
- typedef int flag;
- typedef int ftnlen;
- typedef int ftnint;
-
- /*external read, write*/
- typedef struct
- { flag cierr;
- ftnint ciunit;
- flag ciend;
- char *cifmt;
- ftnint cirec;
- } cilist;
-
- /*internal read, write*/
- typedef struct
- { flag icierr;
- char *iciunit;
- flag iciend;
- char *icifmt;
- ftnint icirlen;
- ftnint icirnum;
- } icilist;
-
- /*open*/
- typedef struct
- { flag oerr;
- ftnint ounit;
- char *ofnm;
- ftnlen ofnmlen;
- char *osta;
- char *oacc;
- char *ofm;
- ftnint orl;
- char *oblnk;
- } olist;
-
- /*close*/
- typedef struct
- { flag cerr;
- ftnint cunit;
- char *csta;
- } cllist;
-
- /*rewind, backspace, endfile*/
- typedef struct
- { flag aerr;
- ftnint aunit;
- } alist;
-
- /* inquire */
- typedef struct
- { flag inerr;
- ftnint inunit;
- char *infile;
- ftnlen infilen;
- ftnint *inex; /*parameters in standard's order*/
- ftnint *inopen;
- ftnint *innum;
- ftnint *innamed;
- char *inname;
- ftnlen innamlen;
- char *inacc;
- ftnlen inacclen;
- char *inseq;
- ftnlen inseqlen;
- char *indir;
- ftnlen indirlen;
- char *infmt;
- ftnlen infmtlen;
- char *inform;
- ftnint informlen;
- char *inunf;
- ftnlen inunflen;
- ftnint *inrecl;
- ftnint *innrec;
- char *inblank;
- ftnlen inblanklen;
- } inlist;
-
- #define VOID void
-
- union Multitype { /* for multiple entry points */
- integer1 g;
- shortint h;
- integer i;
- /* longint j; */
- real r;
- doublereal d;
- complex c;
- doublecomplex z;
- };
-
- typedef union Multitype Multitype;
-
- struct Vardesc { /* for Namelist */
- char *name;
- char *addr;
- ftnlen *dims;
- int type;
- };
- typedef struct Vardesc Vardesc;
-
- struct Namelist {
- char *name;
- Vardesc **vars;
- int nvars;
- };
- typedef struct Namelist Namelist;
-
- #define abs(x) ((x) >= 0 ? (x) : -(x))
- #define dabs(x) (fabs(x))
- #define f2cmin(a,b) ((a) <= (b) ? (a) : (b))
- #define f2cmax(a,b) ((a) >= (b) ? (a) : (b))
- #define dmin(a,b) (f2cmin(a,b))
- #define dmax(a,b) (f2cmax(a,b))
- #define bit_test(a,b) ((a) >> (b) & 1)
- #define bit_clear(a,b) ((a) & ~((uinteger)1 << (b)))
- #define bit_set(a,b) ((a) | ((uinteger)1 << (b)))
-
- #define abort_() { sig_die("Fortran abort routine called", 1); }
- #define c_abs(z) (cabsf(Cf(z)))
- #define c_cos(R,Z) { pCf(R)=ccos(Cf(Z)); }
- #ifdef _MSC_VER
- #define c_div(c, a, b) {Cf(c)._Val[0] = (Cf(a)._Val[0]/Cf(b)._Val[0]); Cf(c)._Val[1]=(Cf(a)._Val[1]/Cf(b)._Val[1]);}
- #define z_div(c, a, b) {Cd(c)._Val[0] = (Cd(a)._Val[0]/Cd(b)._Val[0]); Cd(c)._Val[1]=(Cd(a)._Val[1]/df(b)._Val[1]);}
- #else
- #define c_div(c, a, b) {pCf(c) = Cf(a)/Cf(b);}
- #define z_div(c, a, b) {pCd(c) = Cd(a)/Cd(b);}
- #endif
- #define c_exp(R, Z) {pCf(R) = cexpf(Cf(Z));}
- #define c_log(R, Z) {pCf(R) = clogf(Cf(Z));}
- #define c_sin(R, Z) {pCf(R) = csinf(Cf(Z));}
- //#define c_sqrt(R, Z) {*(R) = csqrtf(Cf(Z));}
- #define c_sqrt(R, Z) {pCf(R) = csqrtf(Cf(Z));}
- #define d_abs(x) (fabs(*(x)))
- #define d_acos(x) (acos(*(x)))
- #define d_asin(x) (asin(*(x)))
- #define d_atan(x) (atan(*(x)))
- #define d_atn2(x, y) (atan2(*(x),*(y)))
- #define d_cnjg(R, Z) { pCd(R) = conj(Cd(Z)); }
- #define r_cnjg(R, Z) { pCf(R) = conjf(Cf(Z)); }
- #define d_cos(x) (cos(*(x)))
- #define d_cosh(x) (cosh(*(x)))
- #define d_dim(__a, __b) ( *(__a) > *(__b) ? *(__a) - *(__b) : 0.0 )
- #define d_exp(x) (exp(*(x)))
- #define d_imag(z) (cimag(Cd(z)))
- #define r_imag(z) (cimagf(Cf(z)))
- #define d_int(__x) (*(__x)>0 ? floor(*(__x)) : -floor(- *(__x)))
- #define r_int(__x) (*(__x)>0 ? floor(*(__x)) : -floor(- *(__x)))
- #define d_lg10(x) ( 0.43429448190325182765 * log(*(x)) )
- #define r_lg10(x) ( 0.43429448190325182765 * log(*(x)) )
- #define d_log(x) (log(*(x)))
- #define d_mod(x, y) (fmod(*(x), *(y)))
- #define u_nint(__x) ((__x)>=0 ? floor((__x) + .5) : -floor(.5 - (__x)))
- #define d_nint(x) u_nint(*(x))
- #define u_sign(__a,__b) ((__b) >= 0 ? ((__a) >= 0 ? (__a) : -(__a)) : -((__a) >= 0 ? (__a) : -(__a)))
- #define d_sign(a,b) u_sign(*(a),*(b))
- #define r_sign(a,b) u_sign(*(a),*(b))
- #define d_sin(x) (sin(*(x)))
- #define d_sinh(x) (sinh(*(x)))
- #define d_sqrt(x) (sqrt(*(x)))
- #define d_tan(x) (tan(*(x)))
- #define d_tanh(x) (tanh(*(x)))
- #define i_abs(x) abs(*(x))
- #define i_dnnt(x) ((integer)u_nint(*(x)))
- #define i_len(s, n) (n)
- #define i_nint(x) ((integer)u_nint(*(x)))
- #define i_sign(a,b) ((integer)u_sign((integer)*(a),(integer)*(b)))
- #define pow_dd(ap, bp) ( pow(*(ap), *(bp)))
- #define pow_si(B,E) spow_ui(*(B),*(E))
- #define pow_ri(B,E) spow_ui(*(B),*(E))
- #define pow_di(B,E) dpow_ui(*(B),*(E))
- #define pow_zi(p, a, b) {pCd(p) = zpow_ui(Cd(a), *(b));}
- #define pow_ci(p, a, b) {pCf(p) = cpow_ui(Cf(a), *(b));}
- #define pow_zz(R,A,B) {pCd(R) = cpow(Cd(A),*(B));}
- #define s_cat(lpp, rpp, rnp, np, llp) { ftnlen i, nc, ll; char *f__rp, *lp; ll = (llp); lp = (lpp); for(i=0; i < (int)*(np); ++i) { nc = ll; if((rnp)[i] < nc) nc = (rnp)[i]; ll -= nc; f__rp = (rpp)[i]; while(--nc >= 0) *lp++ = *(f__rp)++; } while(--ll >= 0) *lp++ = ' '; }
- #define s_cmp(a,b,c,d) ((integer)strncmp((a),(b),f2cmin((c),(d))))
- #define s_copy(A,B,C,D) { int __i,__m; for (__i=0, __m=f2cmin((C),(D)); __i<__m && (B)[__i] != 0; ++__i) (A)[__i] = (B)[__i]; }
- #define sig_die(s, kill) { exit(1); }
- #define s_stop(s, n) {exit(0);}
- static char junk[] = "\n@(#)LIBF77 VERSION 19990503\n";
- #define z_abs(z) (cabs(Cd(z)))
- #define z_exp(R, Z) {pCd(R) = cexp(Cd(Z));}
- #define z_sqrt(R, Z) {pCd(R) = csqrt(Cd(Z));}
- #define myexit_() break;
- #define mycycle() continue;
- #define myceiling(w) {ceil(w)}
- #define myhuge(w) {HUGE_VAL}
- //#define mymaxloc_(w,s,e,n) {if (sizeof(*(w)) == sizeof(double)) dmaxloc_((w),*(s),*(e),n); else dmaxloc_((w),*(s),*(e),n);}
- #define mymaxloc(w,s,e,n) {dmaxloc_(w,*(s),*(e),n)}
-
- /* procedure parameter types for -A and -C++ */
-
- #define F2C_proc_par_types 1
- #ifdef __cplusplus
- typedef logical (*L_fp)(...);
- #else
- typedef logical (*L_fp)();
- #endif
-
- static float spow_ui(float x, integer n) {
- float pow=1.0; unsigned long int u;
- if(n != 0) {
- if(n < 0) n = -n, x = 1/x;
- for(u = n; ; ) {
- if(u & 01) pow *= x;
- if(u >>= 1) x *= x;
- else break;
- }
- }
- return pow;
- }
- static double dpow_ui(double x, integer n) {
- double pow=1.0; unsigned long int u;
- if(n != 0) {
- if(n < 0) n = -n, x = 1/x;
- for(u = n; ; ) {
- if(u & 01) pow *= x;
- if(u >>= 1) x *= x;
- else break;
- }
- }
- return pow;
- }
- #ifdef _MSC_VER
- static _Fcomplex cpow_ui(complex x, integer n) {
- complex pow={1.0,0.0}; unsigned long int u;
- if(n != 0) {
- if(n < 0) n = -n, x.r = 1/x.r, x.i=1/x.i;
- for(u = n; ; ) {
- if(u & 01) pow.r *= x.r, pow.i *= x.i;
- if(u >>= 1) x.r *= x.r, x.i *= x.i;
- else break;
- }
- }
- _Fcomplex p={pow.r, pow.i};
- return p;
- }
- #else
- static _Complex float cpow_ui(_Complex float x, integer n) {
- _Complex float pow=1.0; unsigned long int u;
- if(n != 0) {
- if(n < 0) n = -n, x = 1/x;
- for(u = n; ; ) {
- if(u & 01) pow *= x;
- if(u >>= 1) x *= x;
- else break;
- }
- }
- return pow;
- }
- #endif
- #ifdef _MSC_VER
- static _Dcomplex zpow_ui(_Dcomplex x, integer n) {
- _Dcomplex pow={1.0,0.0}; unsigned long int u;
- if(n != 0) {
- if(n < 0) n = -n, x._Val[0] = 1/x._Val[0], x._Val[1] =1/x._Val[1];
- for(u = n; ; ) {
- if(u & 01) pow._Val[0] *= x._Val[0], pow._Val[1] *= x._Val[1];
- if(u >>= 1) x._Val[0] *= x._Val[0], x._Val[1] *= x._Val[1];
- else break;
- }
- }
- _Dcomplex p = {pow._Val[0], pow._Val[1]};
- return p;
- }
- #else
- static _Complex double zpow_ui(_Complex double x, integer n) {
- _Complex double pow=1.0; unsigned long int u;
- if(n != 0) {
- if(n < 0) n = -n, x = 1/x;
- for(u = n; ; ) {
- if(u & 01) pow *= x;
- if(u >>= 1) x *= x;
- else break;
- }
- }
- return pow;
- }
- #endif
- static integer pow_ii(integer x, integer n) {
- integer pow; unsigned long int u;
- if (n <= 0) {
- if (n == 0 || x == 1) pow = 1;
- else if (x != -1) pow = x == 0 ? 1/x : 0;
- else n = -n;
- }
- if ((n > 0) || !(n == 0 || x == 1 || x != -1)) {
- u = n;
- for(pow = 1; ; ) {
- if(u & 01) pow *= x;
- if(u >>= 1) x *= x;
- else break;
- }
- }
- return pow;
- }
- static integer dmaxloc_(double *w, integer s, integer e, integer *n)
- {
- double m; integer i, mi;
- for(m=w[s-1], mi=s, i=s+1; i<=e; i++)
- if (w[i-1]>m) mi=i ,m=w[i-1];
- return mi-s+1;
- }
- static integer smaxloc_(float *w, integer s, integer e, integer *n)
- {
- float m; integer i, mi;
- for(m=w[s-1], mi=s, i=s+1; i<=e; i++)
- if (w[i-1]>m) mi=i ,m=w[i-1];
- return mi-s+1;
- }
- static inline void cdotc_(complex *z, integer *n_, complex *x, integer *incx_, complex *y, integer *incy_) {
- integer n = *n_, incx = *incx_, incy = *incy_, i;
- #ifdef _MSC_VER
- _Fcomplex zdotc = {0.0, 0.0};
- if (incx == 1 && incy == 1) {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc._Val[0] += conjf(Cf(&x[i]))._Val[0] * Cf(&y[i])._Val[0];
- zdotc._Val[1] += conjf(Cf(&x[i]))._Val[1] * Cf(&y[i])._Val[1];
- }
- } else {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc._Val[0] += conjf(Cf(&x[i*incx]))._Val[0] * Cf(&y[i*incy])._Val[0];
- zdotc._Val[1] += conjf(Cf(&x[i*incx]))._Val[1] * Cf(&y[i*incy])._Val[1];
- }
- }
- pCf(z) = zdotc;
- }
- #else
- _Complex float zdotc = 0.0;
- if (incx == 1 && incy == 1) {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc += conjf(Cf(&x[i])) * Cf(&y[i]);
- }
- } else {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc += conjf(Cf(&x[i*incx])) * Cf(&y[i*incy]);
- }
- }
- pCf(z) = zdotc;
- }
- #endif
- static inline void zdotc_(doublecomplex *z, integer *n_, doublecomplex *x, integer *incx_, doublecomplex *y, integer *incy_) {
- integer n = *n_, incx = *incx_, incy = *incy_, i;
- #ifdef _MSC_VER
- _Dcomplex zdotc = {0.0, 0.0};
- if (incx == 1 && incy == 1) {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc._Val[0] += conj(Cd(&x[i]))._Val[0] * Cd(&y[i])._Val[0];
- zdotc._Val[1] += conj(Cd(&x[i]))._Val[1] * Cd(&y[i])._Val[1];
- }
- } else {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc._Val[0] += conj(Cd(&x[i*incx]))._Val[0] * Cd(&y[i*incy])._Val[0];
- zdotc._Val[1] += conj(Cd(&x[i*incx]))._Val[1] * Cd(&y[i*incy])._Val[1];
- }
- }
- pCd(z) = zdotc;
- }
- #else
- _Complex double zdotc = 0.0;
- if (incx == 1 && incy == 1) {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc += conj(Cd(&x[i])) * Cd(&y[i]);
- }
- } else {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc += conj(Cd(&x[i*incx])) * Cd(&y[i*incy]);
- }
- }
- pCd(z) = zdotc;
- }
- #endif
- static inline void cdotu_(complex *z, integer *n_, complex *x, integer *incx_, complex *y, integer *incy_) {
- integer n = *n_, incx = *incx_, incy = *incy_, i;
- #ifdef _MSC_VER
- _Fcomplex zdotc = {0.0, 0.0};
- if (incx == 1 && incy == 1) {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc._Val[0] += Cf(&x[i])._Val[0] * Cf(&y[i])._Val[0];
- zdotc._Val[1] += Cf(&x[i])._Val[1] * Cf(&y[i])._Val[1];
- }
- } else {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc._Val[0] += Cf(&x[i*incx])._Val[0] * Cf(&y[i*incy])._Val[0];
- zdotc._Val[1] += Cf(&x[i*incx])._Val[1] * Cf(&y[i*incy])._Val[1];
- }
- }
- pCf(z) = zdotc;
- }
- #else
- _Complex float zdotc = 0.0;
- if (incx == 1 && incy == 1) {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc += Cf(&x[i]) * Cf(&y[i]);
- }
- } else {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc += Cf(&x[i*incx]) * Cf(&y[i*incy]);
- }
- }
- pCf(z) = zdotc;
- }
- #endif
- static inline void zdotu_(doublecomplex *z, integer *n_, doublecomplex *x, integer *incx_, doublecomplex *y, integer *incy_) {
- integer n = *n_, incx = *incx_, incy = *incy_, i;
- #ifdef _MSC_VER
- _Dcomplex zdotc = {0.0, 0.0};
- if (incx == 1 && incy == 1) {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc._Val[0] += Cd(&x[i])._Val[0] * Cd(&y[i])._Val[0];
- zdotc._Val[1] += Cd(&x[i])._Val[1] * Cd(&y[i])._Val[1];
- }
- } else {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc._Val[0] += Cd(&x[i*incx])._Val[0] * Cd(&y[i*incy])._Val[0];
- zdotc._Val[1] += Cd(&x[i*incx])._Val[1] * Cd(&y[i*incy])._Val[1];
- }
- }
- pCd(z) = zdotc;
- }
- #else
- _Complex double zdotc = 0.0;
- if (incx == 1 && incy == 1) {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc += Cd(&x[i]) * Cd(&y[i]);
- }
- } else {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc += Cd(&x[i*incx]) * Cd(&y[i*incy]);
- }
- }
- pCd(z) = zdotc;
- }
- #endif
- /* -- translated by f2c (version 20000121).
- You must link the resulting object file with the libraries:
- -lf2c -lm (in that order)
- */
-
-
- /* -- translated by f2c (version 20000121).
- You must link the resulting object file with the libraries:
- -lf2c -lm (in that order)
- */
-
-
-
- /* Table of constant values */
-
- static doublereal c_b15 = -.125;
- static integer c__1 = 1;
- static real c_b49 = 1.f;
- static real c_b72 = -1.f;
-
- /* > \brief \b CBDSQR */
-
- /* =========== DOCUMENTATION =========== */
-
- /* Online html documentation available at */
- /* http://www.netlib.org/lapack/explore-html/ */
-
- /* > \htmlonly */
- /* > Download CBDSQR + dependencies */
- /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/cbdsqr.
- f"> */
- /* > [TGZ]</a> */
- /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/cbdsqr.
- f"> */
- /* > [ZIP]</a> */
- /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/cbdsqr.
- f"> */
- /* > [TXT]</a> */
- /* > \endhtmlonly */
-
- /* Definition: */
- /* =========== */
-
- /* SUBROUTINE CBDSQR( UPLO, N, NCVT, NRU, NCC, D, E, VT, LDVT, U, */
- /* LDU, C, LDC, RWORK, INFO ) */
-
- /* CHARACTER UPLO */
- /* INTEGER INFO, LDC, LDU, LDVT, N, NCC, NCVT, NRU */
- /* REAL D( * ), E( * ), RWORK( * ) */
- /* COMPLEX C( LDC, * ), U( LDU, * ), VT( LDVT, * ) */
-
-
- /* > \par Purpose: */
- /* ============= */
- /* > */
- /* > \verbatim */
- /* > */
- /* > CBDSQR computes the singular values and, optionally, the right and/or */
- /* > left singular vectors from the singular value decomposition (SVD) of */
- /* > a real N-by-N (upper or lower) bidiagonal matrix B using the implicit */
- /* > zero-shift QR algorithm. The SVD of B has the form */
- /* > */
- /* > B = Q * S * P**H */
- /* > */
- /* > where S is the diagonal matrix of singular values, Q is an orthogonal */
- /* > matrix of left singular vectors, and P is an orthogonal matrix of */
- /* > right singular vectors. If left singular vectors are requested, this */
- /* > subroutine actually returns U*Q instead of Q, and, if right singular */
- /* > vectors are requested, this subroutine returns P**H*VT instead of */
- /* > P**H, for given complex input matrices U and VT. When U and VT are */
- /* > the unitary matrices that reduce a general matrix A to bidiagonal */
- /* > form: A = U*B*VT, as computed by CGEBRD, then */
- /* > */
- /* > A = (U*Q) * S * (P**H*VT) */
- /* > */
- /* > is the SVD of A. Optionally, the subroutine may also compute Q**H*C */
- /* > for a given complex input matrix C. */
- /* > */
- /* > See "Computing Small Singular Values of Bidiagonal Matrices With */
- /* > Guaranteed High Relative Accuracy," by J. Demmel and W. Kahan, */
- /* > LAPACK Working Note #3 (or SIAM J. Sci. Statist. Comput. vol. 11, */
- /* > no. 5, pp. 873-912, Sept 1990) and */
- /* > "Accurate singular values and differential qd algorithms," by */
- /* > B. Parlett and V. Fernando, Technical Report CPAM-554, Mathematics */
- /* > Department, University of California at Berkeley, July 1992 */
- /* > for a detailed description of the algorithm. */
- /* > \endverbatim */
-
- /* Arguments: */
- /* ========== */
-
- /* > \param[in] UPLO */
- /* > \verbatim */
- /* > UPLO is CHARACTER*1 */
- /* > = 'U': B is upper bidiagonal; */
- /* > = 'L': B is lower bidiagonal. */
- /* > \endverbatim */
- /* > */
- /* > \param[in] N */
- /* > \verbatim */
- /* > N is INTEGER */
- /* > The order of the matrix B. N >= 0. */
- /* > \endverbatim */
- /* > */
- /* > \param[in] NCVT */
- /* > \verbatim */
- /* > NCVT is INTEGER */
- /* > The number of columns of the matrix VT. NCVT >= 0. */
- /* > \endverbatim */
- /* > */
- /* > \param[in] NRU */
- /* > \verbatim */
- /* > NRU is INTEGER */
- /* > The number of rows of the matrix U. NRU >= 0. */
- /* > \endverbatim */
- /* > */
- /* > \param[in] NCC */
- /* > \verbatim */
- /* > NCC is INTEGER */
- /* > The number of columns of the matrix C. NCC >= 0. */
- /* > \endverbatim */
- /* > */
- /* > \param[in,out] D */
- /* > \verbatim */
- /* > D is REAL array, dimension (N) */
- /* > On entry, the n diagonal elements of the bidiagonal matrix B. */
- /* > On exit, if INFO=0, the singular values of B in decreasing */
- /* > order. */
- /* > \endverbatim */
- /* > */
- /* > \param[in,out] E */
- /* > \verbatim */
- /* > E is REAL array, dimension (N-1) */
- /* > On entry, the N-1 offdiagonal elements of the bidiagonal */
- /* > matrix B. */
- /* > On exit, if INFO = 0, E is destroyed; if INFO > 0, D and E */
- /* > will contain the diagonal and superdiagonal elements of a */
- /* > bidiagonal matrix orthogonally equivalent to the one given */
- /* > as input. */
- /* > \endverbatim */
- /* > */
- /* > \param[in,out] VT */
- /* > \verbatim */
- /* > VT is COMPLEX array, dimension (LDVT, NCVT) */
- /* > On entry, an N-by-NCVT matrix VT. */
- /* > On exit, VT is overwritten by P**H * VT. */
- /* > Not referenced if NCVT = 0. */
- /* > \endverbatim */
- /* > */
- /* > \param[in] LDVT */
- /* > \verbatim */
- /* > LDVT is INTEGER */
- /* > The leading dimension of the array VT. */
- /* > LDVT >= f2cmax(1,N) if NCVT > 0; LDVT >= 1 if NCVT = 0. */
- /* > \endverbatim */
- /* > */
- /* > \param[in,out] U */
- /* > \verbatim */
- /* > U is COMPLEX array, dimension (LDU, N) */
- /* > On entry, an NRU-by-N matrix U. */
- /* > On exit, U is overwritten by U * Q. */
- /* > Not referenced if NRU = 0. */
- /* > \endverbatim */
- /* > */
- /* > \param[in] LDU */
- /* > \verbatim */
- /* > LDU is INTEGER */
- /* > The leading dimension of the array U. LDU >= f2cmax(1,NRU). */
- /* > \endverbatim */
- /* > */
- /* > \param[in,out] C */
- /* > \verbatim */
- /* > C is COMPLEX array, dimension (LDC, NCC) */
- /* > On entry, an N-by-NCC matrix C. */
- /* > On exit, C is overwritten by Q**H * C. */
- /* > Not referenced if NCC = 0. */
- /* > \endverbatim */
- /* > */
- /* > \param[in] LDC */
- /* > \verbatim */
- /* > LDC is INTEGER */
- /* > The leading dimension of the array C. */
- /* > LDC >= f2cmax(1,N) if NCC > 0; LDC >=1 if NCC = 0. */
- /* > \endverbatim */
- /* > */
- /* > \param[out] RWORK */
- /* > \verbatim */
- /* > RWORK is REAL array, dimension (4*N) */
- /* > \endverbatim */
- /* > */
- /* > \param[out] INFO */
- /* > \verbatim */
- /* > INFO is INTEGER */
- /* > = 0: successful exit */
- /* > < 0: If INFO = -i, the i-th argument had an illegal value */
- /* > > 0: the algorithm did not converge; D and E contain the */
- /* > elements of a bidiagonal matrix which is orthogonally */
- /* > similar to the input matrix B; if INFO = i, i */
- /* > elements of E have not converged to zero. */
- /* > \endverbatim */
-
- /* > \par Internal Parameters: */
- /* ========================= */
- /* > */
- /* > \verbatim */
- /* > TOLMUL REAL, default = f2cmax(10,f2cmin(100,EPS**(-1/8))) */
- /* > TOLMUL controls the convergence criterion of the QR loop. */
- /* > If it is positive, TOLMUL*EPS is the desired relative */
- /* > precision in the computed singular values. */
- /* > If it is negative, abs(TOLMUL*EPS*sigma_max) is the */
- /* > desired absolute accuracy in the computed singular */
- /* > values (corresponds to relative accuracy */
- /* > abs(TOLMUL*EPS) in the largest singular value. */
- /* > abs(TOLMUL) should be between 1 and 1/EPS, and preferably */
- /* > between 10 (for fast convergence) and .1/EPS */
- /* > (for there to be some accuracy in the results). */
- /* > Default is to lose at either one eighth or 2 of the */
- /* > available decimal digits in each computed singular value */
- /* > (whichever is smaller). */
- /* > */
- /* > MAXITR INTEGER, default = 6 */
- /* > MAXITR controls the maximum number of passes of the */
- /* > algorithm through its inner loop. The algorithms stops */
- /* > (and so fails to converge) if the number of passes */
- /* > through the inner loop exceeds MAXITR*N**2. */
- /* > \endverbatim */
-
- /* Authors: */
- /* ======== */
-
- /* > \author Univ. of Tennessee */
- /* > \author Univ. of California Berkeley */
- /* > \author Univ. of Colorado Denver */
- /* > \author NAG Ltd. */
-
- /* > \date December 2016 */
-
- /* > \ingroup complexOTHERcomputational */
-
- /* ===================================================================== */
- /* Subroutine */ void cbdsqr_(char *uplo, integer *n, integer *ncvt, integer *
- nru, integer *ncc, real *d__, real *e, complex *vt, integer *ldvt,
- complex *u, integer *ldu, complex *c__, integer *ldc, real *rwork,
- integer *info)
- {
- /* System generated locals */
- integer c_dim1, c_offset, u_dim1, u_offset, vt_dim1, vt_offset, i__1,
- i__2;
- real r__1, r__2, r__3, r__4;
- doublereal d__1;
-
- /* Local variables */
- real abse;
- integer idir;
- real abss;
- integer oldm;
- real cosl;
- integer isub, iter;
- real unfl, sinl, cosr, smin, smax, sinr;
- extern /* Subroutine */ void slas2_(real *, real *, real *, real *, real *)
- ;
- real f, g, h__;
- integer i__, j, m;
- real r__;
- extern logical lsame_(char *, char *);
- real oldcs;
- extern /* Subroutine */ void clasr_(char *, char *, char *, integer *,
- integer *, real *, real *, complex *, integer *);
- integer oldll;
- real shift, sigmn, oldsn;
- extern /* Subroutine */ void cswap_(integer *, complex *, integer *,
- complex *, integer *);
- integer maxit;
- real sminl, sigmx;
- logical lower;
- extern /* Subroutine */ void csrot_(integer *, complex *, integer *,
- complex *, integer *, real *, real *), slasq1_(integer *, real *,
- real *, real *, integer *), slasv2_(real *, real *, real *, real *
- , real *, real *, real *, real *, real *);
- real cs;
- integer ll;
- real sn, mu;
- extern real slamch_(char *);
- extern /* Subroutine */ void csscal_(integer *, real *, complex *, integer
- *);
- extern int xerbla_(char *, integer *, ftnlen);
- real sminoa;
- extern /* Subroutine */ void slartg_(real *, real *, real *, real *, real *
- );
- real thresh;
- logical rotate;
- integer nm1;
- real tolmul;
- integer nm12, nm13, lll;
- real eps, sll, tol;
-
-
- /* -- LAPACK computational routine (version 3.7.0) -- */
- /* -- LAPACK is a software package provided by Univ. of Tennessee, -- */
- /* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
- /* December 2016 */
-
-
- /* ===================================================================== */
-
-
- /* Test the input parameters. */
-
- /* Parameter adjustments */
- --d__;
- --e;
- vt_dim1 = *ldvt;
- vt_offset = 1 + vt_dim1 * 1;
- vt -= vt_offset;
- u_dim1 = *ldu;
- u_offset = 1 + u_dim1 * 1;
- u -= u_offset;
- c_dim1 = *ldc;
- c_offset = 1 + c_dim1 * 1;
- c__ -= c_offset;
- --rwork;
-
- /* Function Body */
- *info = 0;
- lower = lsame_(uplo, "L");
- if (! lsame_(uplo, "U") && ! lower) {
- *info = -1;
- } else if (*n < 0) {
- *info = -2;
- } else if (*ncvt < 0) {
- *info = -3;
- } else if (*nru < 0) {
- *info = -4;
- } else if (*ncc < 0) {
- *info = -5;
- } else if (*ncvt == 0 && *ldvt < 1 || *ncvt > 0 && *ldvt < f2cmax(1,*n)) {
- *info = -9;
- } else if (*ldu < f2cmax(1,*nru)) {
- *info = -11;
- } else if (*ncc == 0 && *ldc < 1 || *ncc > 0 && *ldc < f2cmax(1,*n)) {
- *info = -13;
- }
- if (*info != 0) {
- i__1 = -(*info);
- xerbla_("CBDSQR", &i__1, (ftnlen)6);
- return;
- }
- if (*n == 0) {
- return;
- }
- if (*n == 1) {
- goto L160;
- }
-
- /* ROTATE is true if any singular vectors desired, false otherwise */
-
- rotate = *ncvt > 0 || *nru > 0 || *ncc > 0;
-
- /* If no singular vectors desired, use qd algorithm */
-
- if (! rotate) {
- slasq1_(n, &d__[1], &e[1], &rwork[1], info);
-
- /* If INFO equals 2, dqds didn't finish, try to finish */
-
- if (*info != 2) {
- return;
- }
- *info = 0;
- }
-
- nm1 = *n - 1;
- nm12 = nm1 + nm1;
- nm13 = nm12 + nm1;
- idir = 0;
-
- /* Get machine constants */
-
- eps = slamch_("Epsilon");
- unfl = slamch_("Safe minimum");
-
- /* If matrix lower bidiagonal, rotate to be upper bidiagonal */
- /* by applying Givens rotations on the left */
-
- if (lower) {
- i__1 = *n - 1;
- for (i__ = 1; i__ <= i__1; ++i__) {
- slartg_(&d__[i__], &e[i__], &cs, &sn, &r__);
- d__[i__] = r__;
- e[i__] = sn * d__[i__ + 1];
- d__[i__ + 1] = cs * d__[i__ + 1];
- rwork[i__] = cs;
- rwork[nm1 + i__] = sn;
- /* L10: */
- }
-
- /* Update singular vectors if desired */
-
- if (*nru > 0) {
- clasr_("R", "V", "F", nru, n, &rwork[1], &rwork[*n], &u[u_offset],
- ldu);
- }
- if (*ncc > 0) {
- clasr_("L", "V", "F", n, ncc, &rwork[1], &rwork[*n], &c__[
- c_offset], ldc);
- }
- }
-
- /* Compute singular values to relative accuracy TOL */
- /* (By setting TOL to be negative, algorithm will compute */
- /* singular values to absolute accuracy ABS(TOL)*norm(input matrix)) */
-
- /* Computing MAX */
- /* Computing MIN */
- d__1 = (doublereal) eps;
- r__3 = 100.f, r__4 = pow_dd(&d__1, &c_b15);
- r__1 = 10.f, r__2 = f2cmin(r__3,r__4);
- tolmul = f2cmax(r__1,r__2);
- tol = tolmul * eps;
-
- /* Compute approximate maximum, minimum singular values */
-
- smax = 0.f;
- i__1 = *n;
- for (i__ = 1; i__ <= i__1; ++i__) {
- /* Computing MAX */
- r__2 = smax, r__3 = (r__1 = d__[i__], abs(r__1));
- smax = f2cmax(r__2,r__3);
- /* L20: */
- }
- i__1 = *n - 1;
- for (i__ = 1; i__ <= i__1; ++i__) {
- /* Computing MAX */
- r__2 = smax, r__3 = (r__1 = e[i__], abs(r__1));
- smax = f2cmax(r__2,r__3);
- /* L30: */
- }
- sminl = 0.f;
- if (tol >= 0.f) {
-
- /* Relative accuracy desired */
-
- sminoa = abs(d__[1]);
- if (sminoa == 0.f) {
- goto L50;
- }
- mu = sminoa;
- i__1 = *n;
- for (i__ = 2; i__ <= i__1; ++i__) {
- mu = (r__2 = d__[i__], abs(r__2)) * (mu / (mu + (r__1 = e[i__ - 1]
- , abs(r__1))));
- sminoa = f2cmin(sminoa,mu);
- if (sminoa == 0.f) {
- goto L50;
- }
- /* L40: */
- }
- L50:
- sminoa /= sqrt((real) (*n));
- /* Computing MAX */
- r__1 = tol * sminoa, r__2 = *n * 6 * *n * unfl;
- thresh = f2cmax(r__1,r__2);
- } else {
-
- /* Absolute accuracy desired */
-
- /* Computing MAX */
- r__1 = abs(tol) * smax, r__2 = *n * 6 * *n * unfl;
- thresh = f2cmax(r__1,r__2);
- }
-
- /* Prepare for main iteration loop for the singular values */
- /* (MAXIT is the maximum number of passes through the inner */
- /* loop permitted before nonconvergence signalled.) */
-
- maxit = *n * 6 * *n;
- iter = 0;
- oldll = -1;
- oldm = -1;
-
- /* M points to last element of unconverged part of matrix */
-
- m = *n;
-
- /* Begin main iteration loop */
-
- L60:
-
- /* Check for convergence or exceeding iteration count */
-
- if (m <= 1) {
- goto L160;
- }
- if (iter > maxit) {
- goto L200;
- }
-
- /* Find diagonal block of matrix to work on */
-
- if (tol < 0.f && (r__1 = d__[m], abs(r__1)) <= thresh) {
- d__[m] = 0.f;
- }
- smax = (r__1 = d__[m], abs(r__1));
- smin = smax;
- i__1 = m - 1;
- for (lll = 1; lll <= i__1; ++lll) {
- ll = m - lll;
- abss = (r__1 = d__[ll], abs(r__1));
- abse = (r__1 = e[ll], abs(r__1));
- if (tol < 0.f && abss <= thresh) {
- d__[ll] = 0.f;
- }
- if (abse <= thresh) {
- goto L80;
- }
- smin = f2cmin(smin,abss);
- /* Computing MAX */
- r__1 = f2cmax(smax,abss);
- smax = f2cmax(r__1,abse);
- /* L70: */
- }
- ll = 0;
- goto L90;
- L80:
- e[ll] = 0.f;
-
- /* Matrix splits since E(LL) = 0 */
-
- if (ll == m - 1) {
-
- /* Convergence of bottom singular value, return to top of loop */
-
- --m;
- goto L60;
- }
- L90:
- ++ll;
-
- /* E(LL) through E(M-1) are nonzero, E(LL-1) is zero */
-
- if (ll == m - 1) {
-
- /* 2 by 2 block, handle separately */
-
- slasv2_(&d__[m - 1], &e[m - 1], &d__[m], &sigmn, &sigmx, &sinr, &cosr,
- &sinl, &cosl);
- d__[m - 1] = sigmx;
- e[m - 1] = 0.f;
- d__[m] = sigmn;
-
- /* Compute singular vectors, if desired */
-
- if (*ncvt > 0) {
- csrot_(ncvt, &vt[m - 1 + vt_dim1], ldvt, &vt[m + vt_dim1], ldvt, &
- cosr, &sinr);
- }
- if (*nru > 0) {
- csrot_(nru, &u[(m - 1) * u_dim1 + 1], &c__1, &u[m * u_dim1 + 1], &
- c__1, &cosl, &sinl);
- }
- if (*ncc > 0) {
- csrot_(ncc, &c__[m - 1 + c_dim1], ldc, &c__[m + c_dim1], ldc, &
- cosl, &sinl);
- }
- m += -2;
- goto L60;
- }
-
- /* If working on new submatrix, choose shift direction */
- /* (from larger end diagonal element towards smaller) */
-
- if (ll > oldm || m < oldll) {
- if ((r__1 = d__[ll], abs(r__1)) >= (r__2 = d__[m], abs(r__2))) {
-
- /* Chase bulge from top (big end) to bottom (small end) */
-
- idir = 1;
- } else {
-
- /* Chase bulge from bottom (big end) to top (small end) */
-
- idir = 2;
- }
- }
-
- /* Apply convergence tests */
-
- if (idir == 1) {
-
- /* Run convergence test in forward direction */
- /* First apply standard test to bottom of matrix */
-
- if ((r__2 = e[m - 1], abs(r__2)) <= abs(tol) * (r__1 = d__[m], abs(
- r__1)) || tol < 0.f && (r__3 = e[m - 1], abs(r__3)) <= thresh)
- {
- e[m - 1] = 0.f;
- goto L60;
- }
-
- if (tol >= 0.f) {
-
- /* If relative accuracy desired, */
- /* apply convergence criterion forward */
-
- mu = (r__1 = d__[ll], abs(r__1));
- sminl = mu;
- i__1 = m - 1;
- for (lll = ll; lll <= i__1; ++lll) {
- if ((r__1 = e[lll], abs(r__1)) <= tol * mu) {
- e[lll] = 0.f;
- goto L60;
- }
- mu = (r__2 = d__[lll + 1], abs(r__2)) * (mu / (mu + (r__1 = e[
- lll], abs(r__1))));
- sminl = f2cmin(sminl,mu);
- /* L100: */
- }
- }
-
- } else {
-
- /* Run convergence test in backward direction */
- /* First apply standard test to top of matrix */
-
- if ((r__2 = e[ll], abs(r__2)) <= abs(tol) * (r__1 = d__[ll], abs(r__1)
- ) || tol < 0.f && (r__3 = e[ll], abs(r__3)) <= thresh) {
- e[ll] = 0.f;
- goto L60;
- }
-
- if (tol >= 0.f) {
-
- /* If relative accuracy desired, */
- /* apply convergence criterion backward */
-
- mu = (r__1 = d__[m], abs(r__1));
- sminl = mu;
- i__1 = ll;
- for (lll = m - 1; lll >= i__1; --lll) {
- if ((r__1 = e[lll], abs(r__1)) <= tol * mu) {
- e[lll] = 0.f;
- goto L60;
- }
- mu = (r__2 = d__[lll], abs(r__2)) * (mu / (mu + (r__1 = e[lll]
- , abs(r__1))));
- sminl = f2cmin(sminl,mu);
- /* L110: */
- }
- }
- }
- oldll = ll;
- oldm = m;
-
- /* Compute shift. First, test if shifting would ruin relative */
- /* accuracy, and if so set the shift to zero. */
-
- /* Computing MAX */
- r__1 = eps, r__2 = tol * .01f;
- if (tol >= 0.f && *n * tol * (sminl / smax) <= f2cmax(r__1,r__2)) {
-
- /* Use a zero shift to avoid loss of relative accuracy */
-
- shift = 0.f;
- } else {
-
- /* Compute the shift from 2-by-2 block at end of matrix */
-
- if (idir == 1) {
- sll = (r__1 = d__[ll], abs(r__1));
- slas2_(&d__[m - 1], &e[m - 1], &d__[m], &shift, &r__);
- } else {
- sll = (r__1 = d__[m], abs(r__1));
- slas2_(&d__[ll], &e[ll], &d__[ll + 1], &shift, &r__);
- }
-
- /* Test if shift negligible, and if so set to zero */
-
- if (sll > 0.f) {
- /* Computing 2nd power */
- r__1 = shift / sll;
- if (r__1 * r__1 < eps) {
- shift = 0.f;
- }
- }
- }
-
- /* Increment iteration count */
-
- iter = iter + m - ll;
-
- /* If SHIFT = 0, do simplified QR iteration */
-
- if (shift == 0.f) {
- if (idir == 1) {
-
- /* Chase bulge from top to bottom */
- /* Save cosines and sines for later singular vector updates */
-
- cs = 1.f;
- oldcs = 1.f;
- i__1 = m - 1;
- for (i__ = ll; i__ <= i__1; ++i__) {
- r__1 = d__[i__] * cs;
- slartg_(&r__1, &e[i__], &cs, &sn, &r__);
- if (i__ > ll) {
- e[i__ - 1] = oldsn * r__;
- }
- r__1 = oldcs * r__;
- r__2 = d__[i__ + 1] * sn;
- slartg_(&r__1, &r__2, &oldcs, &oldsn, &d__[i__]);
- rwork[i__ - ll + 1] = cs;
- rwork[i__ - ll + 1 + nm1] = sn;
- rwork[i__ - ll + 1 + nm12] = oldcs;
- rwork[i__ - ll + 1 + nm13] = oldsn;
- /* L120: */
- }
- h__ = d__[m] * cs;
- d__[m] = h__ * oldcs;
- e[m - 1] = h__ * oldsn;
-
- /* Update singular vectors */
-
- if (*ncvt > 0) {
- i__1 = m - ll + 1;
- clasr_("L", "V", "F", &i__1, ncvt, &rwork[1], &rwork[*n], &vt[
- ll + vt_dim1], ldvt);
- }
- if (*nru > 0) {
- i__1 = m - ll + 1;
- clasr_("R", "V", "F", nru, &i__1, &rwork[nm12 + 1], &rwork[
- nm13 + 1], &u[ll * u_dim1 + 1], ldu);
- }
- if (*ncc > 0) {
- i__1 = m - ll + 1;
- clasr_("L", "V", "F", &i__1, ncc, &rwork[nm12 + 1], &rwork[
- nm13 + 1], &c__[ll + c_dim1], ldc);
- }
-
- /* Test convergence */
-
- if ((r__1 = e[m - 1], abs(r__1)) <= thresh) {
- e[m - 1] = 0.f;
- }
-
- } else {
-
- /* Chase bulge from bottom to top */
- /* Save cosines and sines for later singular vector updates */
-
- cs = 1.f;
- oldcs = 1.f;
- i__1 = ll + 1;
- for (i__ = m; i__ >= i__1; --i__) {
- r__1 = d__[i__] * cs;
- slartg_(&r__1, &e[i__ - 1], &cs, &sn, &r__);
- if (i__ < m) {
- e[i__] = oldsn * r__;
- }
- r__1 = oldcs * r__;
- r__2 = d__[i__ - 1] * sn;
- slartg_(&r__1, &r__2, &oldcs, &oldsn, &d__[i__]);
- rwork[i__ - ll] = cs;
- rwork[i__ - ll + nm1] = -sn;
- rwork[i__ - ll + nm12] = oldcs;
- rwork[i__ - ll + nm13] = -oldsn;
- /* L130: */
- }
- h__ = d__[ll] * cs;
- d__[ll] = h__ * oldcs;
- e[ll] = h__ * oldsn;
-
- /* Update singular vectors */
-
- if (*ncvt > 0) {
- i__1 = m - ll + 1;
- clasr_("L", "V", "B", &i__1, ncvt, &rwork[nm12 + 1], &rwork[
- nm13 + 1], &vt[ll + vt_dim1], ldvt);
- }
- if (*nru > 0) {
- i__1 = m - ll + 1;
- clasr_("R", "V", "B", nru, &i__1, &rwork[1], &rwork[*n], &u[
- ll * u_dim1 + 1], ldu);
- }
- if (*ncc > 0) {
- i__1 = m - ll + 1;
- clasr_("L", "V", "B", &i__1, ncc, &rwork[1], &rwork[*n], &c__[
- ll + c_dim1], ldc);
- }
-
- /* Test convergence */
-
- if ((r__1 = e[ll], abs(r__1)) <= thresh) {
- e[ll] = 0.f;
- }
- }
- } else {
-
- /* Use nonzero shift */
-
- if (idir == 1) {
-
- /* Chase bulge from top to bottom */
- /* Save cosines and sines for later singular vector updates */
-
- f = ((r__1 = d__[ll], abs(r__1)) - shift) * (r_sign(&c_b49, &d__[
- ll]) + shift / d__[ll]);
- g = e[ll];
- i__1 = m - 1;
- for (i__ = ll; i__ <= i__1; ++i__) {
- slartg_(&f, &g, &cosr, &sinr, &r__);
- if (i__ > ll) {
- e[i__ - 1] = r__;
- }
- f = cosr * d__[i__] + sinr * e[i__];
- e[i__] = cosr * e[i__] - sinr * d__[i__];
- g = sinr * d__[i__ + 1];
- d__[i__ + 1] = cosr * d__[i__ + 1];
- slartg_(&f, &g, &cosl, &sinl, &r__);
- d__[i__] = r__;
- f = cosl * e[i__] + sinl * d__[i__ + 1];
- d__[i__ + 1] = cosl * d__[i__ + 1] - sinl * e[i__];
- if (i__ < m - 1) {
- g = sinl * e[i__ + 1];
- e[i__ + 1] = cosl * e[i__ + 1];
- }
- rwork[i__ - ll + 1] = cosr;
- rwork[i__ - ll + 1 + nm1] = sinr;
- rwork[i__ - ll + 1 + nm12] = cosl;
- rwork[i__ - ll + 1 + nm13] = sinl;
- /* L140: */
- }
- e[m - 1] = f;
-
- /* Update singular vectors */
-
- if (*ncvt > 0) {
- i__1 = m - ll + 1;
- clasr_("L", "V", "F", &i__1, ncvt, &rwork[1], &rwork[*n], &vt[
- ll + vt_dim1], ldvt);
- }
- if (*nru > 0) {
- i__1 = m - ll + 1;
- clasr_("R", "V", "F", nru, &i__1, &rwork[nm12 + 1], &rwork[
- nm13 + 1], &u[ll * u_dim1 + 1], ldu);
- }
- if (*ncc > 0) {
- i__1 = m - ll + 1;
- clasr_("L", "V", "F", &i__1, ncc, &rwork[nm12 + 1], &rwork[
- nm13 + 1], &c__[ll + c_dim1], ldc);
- }
-
- /* Test convergence */
-
- if ((r__1 = e[m - 1], abs(r__1)) <= thresh) {
- e[m - 1] = 0.f;
- }
-
- } else {
-
- /* Chase bulge from bottom to top */
- /* Save cosines and sines for later singular vector updates */
-
- f = ((r__1 = d__[m], abs(r__1)) - shift) * (r_sign(&c_b49, &d__[m]
- ) + shift / d__[m]);
- g = e[m - 1];
- i__1 = ll + 1;
- for (i__ = m; i__ >= i__1; --i__) {
- slartg_(&f, &g, &cosr, &sinr, &r__);
- if (i__ < m) {
- e[i__] = r__;
- }
- f = cosr * d__[i__] + sinr * e[i__ - 1];
- e[i__ - 1] = cosr * e[i__ - 1] - sinr * d__[i__];
- g = sinr * d__[i__ - 1];
- d__[i__ - 1] = cosr * d__[i__ - 1];
- slartg_(&f, &g, &cosl, &sinl, &r__);
- d__[i__] = r__;
- f = cosl * e[i__ - 1] + sinl * d__[i__ - 1];
- d__[i__ - 1] = cosl * d__[i__ - 1] - sinl * e[i__ - 1];
- if (i__ > ll + 1) {
- g = sinl * e[i__ - 2];
- e[i__ - 2] = cosl * e[i__ - 2];
- }
- rwork[i__ - ll] = cosr;
- rwork[i__ - ll + nm1] = -sinr;
- rwork[i__ - ll + nm12] = cosl;
- rwork[i__ - ll + nm13] = -sinl;
- /* L150: */
- }
- e[ll] = f;
-
- /* Test convergence */
-
- if ((r__1 = e[ll], abs(r__1)) <= thresh) {
- e[ll] = 0.f;
- }
-
- /* Update singular vectors if desired */
-
- if (*ncvt > 0) {
- i__1 = m - ll + 1;
- clasr_("L", "V", "B", &i__1, ncvt, &rwork[nm12 + 1], &rwork[
- nm13 + 1], &vt[ll + vt_dim1], ldvt);
- }
- if (*nru > 0) {
- i__1 = m - ll + 1;
- clasr_("R", "V", "B", nru, &i__1, &rwork[1], &rwork[*n], &u[
- ll * u_dim1 + 1], ldu);
- }
- if (*ncc > 0) {
- i__1 = m - ll + 1;
- clasr_("L", "V", "B", &i__1, ncc, &rwork[1], &rwork[*n], &c__[
- ll + c_dim1], ldc);
- }
- }
- }
-
- /* QR iteration finished, go back and check convergence */
-
- goto L60;
-
- /* All singular values converged, so make them positive */
-
- L160:
- i__1 = *n;
- for (i__ = 1; i__ <= i__1; ++i__) {
- if (d__[i__] < 0.f) {
- d__[i__] = -d__[i__];
-
- /* Change sign of singular vectors, if desired */
-
- if (*ncvt > 0) {
- csscal_(ncvt, &c_b72, &vt[i__ + vt_dim1], ldvt);
- }
- }
- /* L170: */
- }
-
- /* Sort the singular values into decreasing order (insertion sort on */
- /* singular values, but only one transposition per singular vector) */
-
- i__1 = *n - 1;
- for (i__ = 1; i__ <= i__1; ++i__) {
-
- /* Scan for smallest D(I) */
-
- isub = 1;
- smin = d__[1];
- i__2 = *n + 1 - i__;
- for (j = 2; j <= i__2; ++j) {
- if (d__[j] <= smin) {
- isub = j;
- smin = d__[j];
- }
- /* L180: */
- }
- if (isub != *n + 1 - i__) {
-
- /* Swap singular values and vectors */
-
- d__[isub] = d__[*n + 1 - i__];
- d__[*n + 1 - i__] = smin;
- if (*ncvt > 0) {
- cswap_(ncvt, &vt[isub + vt_dim1], ldvt, &vt[*n + 1 - i__ +
- vt_dim1], ldvt);
- }
- if (*nru > 0) {
- cswap_(nru, &u[isub * u_dim1 + 1], &c__1, &u[(*n + 1 - i__) *
- u_dim1 + 1], &c__1);
- }
- if (*ncc > 0) {
- cswap_(ncc, &c__[isub + c_dim1], ldc, &c__[*n + 1 - i__ +
- c_dim1], ldc);
- }
- }
- /* L190: */
- }
- goto L220;
-
- /* Maximum number of iterations exceeded, failure to converge */
-
- L200:
- *info = 0;
- i__1 = *n - 1;
- for (i__ = 1; i__ <= i__1; ++i__) {
- if (e[i__] != 0.f) {
- ++(*info);
- }
- /* L210: */
- }
- L220:
- return;
-
- /* End of CBDSQR */
-
- } /* cbdsqr_ */
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